summaryrefslogtreecommitdiff
path: root/drivers/rtc/rtc-ds3232.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/rtc/rtc-ds3232.c')
-rw-r--r--drivers/rtc/rtc-ds3232.c476
1 files changed, 283 insertions, 193 deletions
diff --git a/drivers/rtc/rtc-ds3232.c b/drivers/rtc/rtc-ds3232.c
index 4e99ace66f74..7edc889729c5 100644
--- a/drivers/rtc/rtc-ds3232.c
+++ b/drivers/rtc/rtc-ds3232.c
@@ -1,19 +1,15 @@
/*
- * RTC client/driver for the Maxim/Dallas DS3232 Real-Time Clock over I2C
+ * RTC client/driver for the Maxim/Dallas DS3232/DS3234 Real-Time Clock
*
* Copyright (C) 2009-2011 Freescale Semiconductor.
* Author: Jack Lan <jack.lan@freescale.com>
+ * Copyright (C) 2008 MIMOMax Wireless Ltd.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
-/*
- * It would be more efficient to use i2c msgs/i2c_transfer directly but, as
- * recommened in .../Documentation/i2c/writing-clients section
- * "Sending and receiving", using SMBus level communication is preferred.
- */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
@@ -21,10 +17,11 @@
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/i2c.h>
+#include <linux/spi/spi.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
-#include <linux/workqueue.h>
#include <linux/slab.h>
+#include <linux/regmap.h>
#define DS3232_REG_SECONDS 0x00
#define DS3232_REG_MINUTES 0x01
@@ -50,39 +47,33 @@
# define DS3232_REG_SR_A1F 0x01
struct ds3232 {
- struct i2c_client *client;
+ struct device *dev;
+ struct regmap *regmap;
+ int irq;
struct rtc_device *rtc;
- struct work_struct work;
- /* The mutex protects alarm operations, and prevents a race
- * between the enable_irq() in the workqueue and the free_irq()
- * in the remove function.
- */
- struct mutex mutex;
bool suspended;
- int exiting;
};
-static struct i2c_driver ds3232_driver;
-
-static int ds3232_check_rtc_status(struct i2c_client *client)
+static int ds3232_check_rtc_status(struct device *dev)
{
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
int ret = 0;
int control, stat;
- stat = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
- if (stat < 0)
- return stat;
+ ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+ if (ret)
+ return ret;
if (stat & DS3232_REG_SR_OSF)
- dev_warn(&client->dev,
+ dev_warn(dev,
"oscillator discontinuity flagged, "
"time unreliable\n");
stat &= ~(DS3232_REG_SR_OSF | DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
- ret = i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
- if (ret < 0)
+ ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
+ if (ret)
return ret;
/* If the alarm is pending, clear it before requesting
@@ -90,31 +81,28 @@ static int ds3232_check_rtc_status(struct i2c_client *client)
* before everything is initialized.
*/
- control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
- if (control < 0)
- return control;
+ ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+ if (ret)
+ return ret;
control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
control |= DS3232_REG_CR_INTCN;
- return i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+ return regmap_write(ds3232->regmap, DS3232_REG_CR, control);
}
static int ds3232_read_time(struct device *dev, struct rtc_time *time)
{
- struct i2c_client *client = to_i2c_client(dev);
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
int ret;
u8 buf[7];
unsigned int year, month, day, hour, minute, second;
unsigned int week, twelve_hr, am_pm;
unsigned int century, add_century = 0;
- ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_SECONDS, 7, buf);
-
- if (ret < 0)
+ ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
+ if (ret)
return ret;
- if (ret < 7)
- return -EIO;
second = buf[0];
minute = buf[1];
@@ -159,7 +147,7 @@ static int ds3232_read_time(struct device *dev, struct rtc_time *time)
static int ds3232_set_time(struct device *dev, struct rtc_time *time)
{
- struct i2c_client *client = to_i2c_client(dev);
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
u8 buf[7];
/* Extract time from rtc_time and load into ds3232*/
@@ -179,8 +167,7 @@ static int ds3232_set_time(struct device *dev, struct rtc_time *time)
buf[6] = bin2bcd(time->tm_year);
}
- return i2c_smbus_write_i2c_block_data(client,
- DS3232_REG_SECONDS, 7, buf);
+ return regmap_bulk_write(ds3232->regmap, DS3232_REG_SECONDS, buf, 7);
}
/*
@@ -190,24 +177,19 @@ static int ds3232_set_time(struct device *dev, struct rtc_time *time)
*/
static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct ds3232 *ds3232 = i2c_get_clientdata(client);
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
int control, stat;
int ret;
u8 buf[4];
- mutex_lock(&ds3232->mutex);
-
- ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
- if (ret < 0)
+ ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+ if (ret)
goto out;
- stat = ret;
- ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
- if (ret < 0)
+ ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+ if (ret)
goto out;
- control = ret;
- ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
- if (ret < 0)
+ ret = regmap_bulk_read(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
+ if (ret)
goto out;
alarm->time.tm_sec = bcd2bin(buf[0] & 0x7F);
@@ -226,7 +208,6 @@ static int ds3232_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
ret = 0;
out:
- mutex_unlock(&ds3232->mutex);
return ret;
}
@@ -236,166 +217,129 @@ out:
*/
static int ds3232_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct ds3232 *ds3232 = i2c_get_clientdata(client);
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
int control, stat;
int ret;
u8 buf[4];
- if (client->irq <= 0)
+ if (ds3232->irq <= 0)
return -EINVAL;
- mutex_lock(&ds3232->mutex);
-
buf[0] = bin2bcd(alarm->time.tm_sec);
buf[1] = bin2bcd(alarm->time.tm_min);
buf[2] = bin2bcd(alarm->time.tm_hour);
buf[3] = bin2bcd(alarm->time.tm_mday);
/* clear alarm interrupt enable bit */
- ret = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
- if (ret < 0)
+ ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+ if (ret)
goto out;
- control = ret;
control &= ~(DS3232_REG_CR_A1IE | DS3232_REG_CR_A2IE);
- ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
- if (ret < 0)
+ ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
+ if (ret)
goto out;
/* clear any pending alarm flag */
- ret = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
- if (ret < 0)
+ ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+ if (ret)
goto out;
- stat = ret;
stat &= ~(DS3232_REG_SR_A1F | DS3232_REG_SR_A2F);
- ret = i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
- if (ret < 0)
+ ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
+ if (ret)
goto out;
- ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
+ ret = regmap_bulk_write(ds3232->regmap, DS3232_REG_ALARM1, buf, 4);
+ if (ret)
+ goto out;
if (alarm->enabled) {
control |= DS3232_REG_CR_A1IE;
- ret = i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+ ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
}
out:
- mutex_unlock(&ds3232->mutex);
return ret;
}
-static void ds3232_update_alarm(struct i2c_client *client)
+static int ds3232_update_alarm(struct device *dev, unsigned int enabled)
{
- struct ds3232 *ds3232 = i2c_get_clientdata(client);
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
int control;
int ret;
- u8 buf[4];
-
- mutex_lock(&ds3232->mutex);
-
- ret = i2c_smbus_read_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
- if (ret < 0)
- goto unlock;
-
- buf[0] = bcd2bin(buf[0]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
- 0x80 : buf[0];
- buf[1] = bcd2bin(buf[1]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
- 0x80 : buf[1];
- buf[2] = bcd2bin(buf[2]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
- 0x80 : buf[2];
- buf[3] = bcd2bin(buf[3]) < 0 || (ds3232->rtc->irq_data & RTC_UF) ?
- 0x80 : buf[3];
-
- ret = i2c_smbus_write_i2c_block_data(client, DS3232_REG_ALARM1, 4, buf);
- if (ret < 0)
- goto unlock;
- control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
- if (control < 0)
- goto unlock;
+ ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+ if (ret)
+ return ret;
- if (ds3232->rtc->irq_data & (RTC_AF | RTC_UF))
+ if (enabled)
/* enable alarm1 interrupt */
control |= DS3232_REG_CR_A1IE;
else
/* disable alarm1 interrupt */
control &= ~(DS3232_REG_CR_A1IE);
- i2c_smbus_write_byte_data(client, DS3232_REG_CR, control);
+ ret = regmap_write(ds3232->regmap, DS3232_REG_CR, control);
-unlock:
- mutex_unlock(&ds3232->mutex);
+ return ret;
}
static int ds3232_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct ds3232 *ds3232 = i2c_get_clientdata(client);
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
- if (client->irq <= 0)
+ if (ds3232->irq <= 0)
return -EINVAL;
- if (enabled)
- ds3232->rtc->irq_data |= RTC_AF;
- else
- ds3232->rtc->irq_data &= ~RTC_AF;
-
- ds3232_update_alarm(client);
- return 0;
+ return ds3232_update_alarm(dev, enabled);
}
static irqreturn_t ds3232_irq(int irq, void *dev_id)
{
- struct i2c_client *client = dev_id;
- struct ds3232 *ds3232 = i2c_get_clientdata(client);
-
- disable_irq_nosync(irq);
-
- /*
- * If rtc as a wakeup source, can't schedule the work
- * at system resume flow, because at this time the i2c bus
- * has not been resumed.
- */
- if (!ds3232->suspended)
- schedule_work(&ds3232->work);
-
- return IRQ_HANDLED;
-}
-
-static void ds3232_work(struct work_struct *work)
-{
- struct ds3232 *ds3232 = container_of(work, struct ds3232, work);
- struct i2c_client *client = ds3232->client;
+ struct device *dev = dev_id;
+ struct ds3232 *ds3232 = dev_get_drvdata(dev);
+ struct mutex *lock = &ds3232->rtc->ops_lock;
+ int ret;
int stat, control;
- mutex_lock(&ds3232->mutex);
+ mutex_lock(lock);
- stat = i2c_smbus_read_byte_data(client, DS3232_REG_SR);
- if (stat < 0)
+ ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
+ if (ret)
goto unlock;
if (stat & DS3232_REG_SR_A1F) {
- control = i2c_smbus_read_byte_data(client, DS3232_REG_CR);
- if (control < 0) {
- pr_warn("Read Control Register error - Disable IRQ%d\n",
- client->irq);
+ ret = regmap_read(ds3232->regmap, DS3232_REG_CR, &control);
+ if (ret) {
+ dev_warn(ds3232->dev,
+ "Read Control Register error %d\n", ret);
} else {
/* disable alarm1 interrupt */
control &= ~(DS3232_REG_CR_A1IE);
- i2c_smbus_write_byte_data(client, DS3232_REG_CR,
- control);
+ ret = regmap_write(ds3232->regmap, DS3232_REG_CR,
+ control);
+ if (ret) {
+ dev_warn(ds3232->dev,
+ "Write Control Register error %d\n",
+ ret);
+ goto unlock;
+ }
/* clear the alarm pend flag */
stat &= ~DS3232_REG_SR_A1F;
- i2c_smbus_write_byte_data(client, DS3232_REG_SR, stat);
+ ret = regmap_write(ds3232->regmap, DS3232_REG_SR, stat);
+ if (ret) {
+ dev_warn(ds3232->dev,
+ "Write Status Register error %d\n",
+ ret);
+ goto unlock;
+ }
rtc_update_irq(ds3232->rtc, 1, RTC_AF | RTC_IRQF);
-
- if (!ds3232->exiting)
- enable_irq(client->irq);
}
}
unlock:
- mutex_unlock(&ds3232->mutex);
+ mutex_unlock(lock);
+
+ return IRQ_HANDLED;
}
static const struct rtc_class_ops ds3232_rtc_ops = {
@@ -406,67 +350,50 @@ static const struct rtc_class_ops ds3232_rtc_ops = {
.alarm_irq_enable = ds3232_alarm_irq_enable,
};
-static int ds3232_probe(struct i2c_client *client,
- const struct i2c_device_id *id)
+static int ds3232_probe(struct device *dev, struct regmap *regmap, int irq,
+ const char *name)
{
struct ds3232 *ds3232;
int ret;
- ds3232 = devm_kzalloc(&client->dev, sizeof(struct ds3232), GFP_KERNEL);
+ ds3232 = devm_kzalloc(dev, sizeof(*ds3232), GFP_KERNEL);
if (!ds3232)
return -ENOMEM;
- ds3232->client = client;
- i2c_set_clientdata(client, ds3232);
-
- INIT_WORK(&ds3232->work, ds3232_work);
- mutex_init(&ds3232->mutex);
+ ds3232->regmap = regmap;
+ ds3232->irq = irq;
+ ds3232->dev = dev;
+ dev_set_drvdata(dev, ds3232);
- ret = ds3232_check_rtc_status(client);
+ ret = ds3232_check_rtc_status(dev);
if (ret)
return ret;
- if (client->irq > 0) {
- ret = devm_request_irq(&client->dev, client->irq, ds3232_irq,
- IRQF_SHARED, "ds3232", client);
+ if (ds3232->irq > 0) {
+ ret = devm_request_threaded_irq(dev, ds3232->irq, NULL,
+ ds3232_irq,
+ IRQF_SHARED | IRQF_ONESHOT,
+ name, dev);
if (ret) {
- dev_err(&client->dev, "unable to request IRQ\n");
- }
- device_init_wakeup(&client->dev, 1);
- }
- ds3232->rtc = devm_rtc_device_register(&client->dev, client->name,
- &ds3232_rtc_ops, THIS_MODULE);
- return PTR_ERR_OR_ZERO(ds3232->rtc);
-}
-
-static int ds3232_remove(struct i2c_client *client)
-{
- struct ds3232 *ds3232 = i2c_get_clientdata(client);
-
- if (client->irq > 0) {
- mutex_lock(&ds3232->mutex);
- ds3232->exiting = 1;
- mutex_unlock(&ds3232->mutex);
-
- devm_free_irq(&client->dev, client->irq, client);
- cancel_work_sync(&ds3232->work);
+ ds3232->irq = 0;
+ dev_err(dev, "unable to request IRQ\n");
+ } else
+ device_init_wakeup(dev, 1);
}
+ ds3232->rtc = devm_rtc_device_register(dev, name, &ds3232_rtc_ops,
+ THIS_MODULE);
- return 0;
+ return PTR_ERR_OR_ZERO(ds3232->rtc);
}
#ifdef CONFIG_PM_SLEEP
static int ds3232_suspend(struct device *dev)
{
struct ds3232 *ds3232 = dev_get_drvdata(dev);
- struct i2c_client *client = to_i2c_client(dev);
- if (device_can_wakeup(dev)) {
- ds3232->suspended = true;
- if (irq_set_irq_wake(client->irq, 1)) {
+ if (device_may_wakeup(dev)) {
+ if (enable_irq_wake(ds3232->irq))
dev_warn_once(dev, "Cannot set wakeup source\n");
- ds3232->suspended = false;
- }
}
return 0;
@@ -475,16 +402,9 @@ static int ds3232_suspend(struct device *dev)
static int ds3232_resume(struct device *dev)
{
struct ds3232 *ds3232 = dev_get_drvdata(dev);
- struct i2c_client *client = to_i2c_client(dev);
- if (ds3232->suspended) {
- ds3232->suspended = false;
-
- /* Clear the hardware alarm pend flag */
- schedule_work(&ds3232->work);
-
- irq_set_irq_wake(client->irq, 0);
- }
+ if (device_may_wakeup(dev))
+ disable_irq_wake(ds3232->irq);
return 0;
}
@@ -494,6 +414,27 @@ static const struct dev_pm_ops ds3232_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(ds3232_suspend, ds3232_resume)
};
+#if IS_ENABLED(CONFIG_I2C)
+
+static int ds3232_i2c_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct regmap *regmap;
+ static const struct regmap_config config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ };
+
+ regmap = devm_regmap_init_i2c(client, &config);
+ if (IS_ERR(regmap)) {
+ dev_err(&client->dev, "%s: regmap allocation failed: %ld\n",
+ __func__, PTR_ERR(regmap));
+ return PTR_ERR(regmap);
+ }
+
+ return ds3232_probe(&client->dev, regmap, client->irq, client->name);
+}
+
static const struct i2c_device_id ds3232_id[] = {
{ "ds3232", 0 },
{ }
@@ -505,13 +446,162 @@ static struct i2c_driver ds3232_driver = {
.name = "rtc-ds3232",
.pm = &ds3232_pm_ops,
},
- .probe = ds3232_probe,
- .remove = ds3232_remove,
+ .probe = ds3232_i2c_probe,
.id_table = ds3232_id,
};
-module_i2c_driver(ds3232_driver);
+static int ds3232_register_driver(void)
+{
+ return i2c_add_driver(&ds3232_driver);
+}
+
+static void ds3232_unregister_driver(void)
+{
+ i2c_del_driver(&ds3232_driver);
+}
+
+#else
+
+static int ds3232_register_driver(void)
+{
+ return 0;
+}
+
+static void ds3232_unregister_driver(void)
+{
+}
+
+#endif
+
+#if IS_ENABLED(CONFIG_SPI_MASTER)
+
+static int ds3234_probe(struct spi_device *spi)
+{
+ int res;
+ unsigned int tmp;
+ static const struct regmap_config config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .write_flag_mask = 0x80,
+ };
+ struct regmap *regmap;
+
+ regmap = devm_regmap_init_spi(spi, &config);
+ if (IS_ERR(regmap)) {
+ dev_err(&spi->dev, "%s: regmap allocation failed: %ld\n",
+ __func__, PTR_ERR(regmap));
+ return PTR_ERR(regmap);
+ }
+
+ spi->mode = SPI_MODE_3;
+ spi->bits_per_word = 8;
+ spi_setup(spi);
+
+ res = regmap_read(regmap, DS3232_REG_SECONDS, &tmp);
+ if (res)
+ return res;
+
+ /* Control settings
+ *
+ * CONTROL_REG
+ * BIT 7 6 5 4 3 2 1 0
+ * EOSC BBSQW CONV RS2 RS1 INTCN A2IE A1IE
+ *
+ * 0 0 0 1 1 1 0 0
+ *
+ * CONTROL_STAT_REG
+ * BIT 7 6 5 4 3 2 1 0
+ * OSF BB32kHz CRATE1 CRATE0 EN32kHz BSY A2F A1F
+ *
+ * 1 0 0 0 1 0 0 0
+ */
+ res = regmap_read(regmap, DS3232_REG_CR, &tmp);
+ if (res)
+ return res;
+ res = regmap_write(regmap, DS3232_REG_CR, tmp & 0x1c);
+ if (res)
+ return res;
+
+ res = regmap_read(regmap, DS3232_REG_SR, &tmp);
+ if (res)
+ return res;
+ res = regmap_write(regmap, DS3232_REG_SR, tmp & 0x88);
+ if (res)
+ return res;
+
+ /* Print our settings */
+ res = regmap_read(regmap, DS3232_REG_CR, &tmp);
+ if (res)
+ return res;
+ dev_info(&spi->dev, "Control Reg: 0x%02x\n", tmp);
+
+ res = regmap_read(regmap, DS3232_REG_SR, &tmp);
+ if (res)
+ return res;
+ dev_info(&spi->dev, "Ctrl/Stat Reg: 0x%02x\n", tmp);
+
+ return ds3232_probe(&spi->dev, regmap, spi->irq, "ds3234");
+}
+
+static struct spi_driver ds3234_driver = {
+ .driver = {
+ .name = "ds3234",
+ },
+ .probe = ds3234_probe,
+};
+
+static int ds3234_register_driver(void)
+{
+ return spi_register_driver(&ds3234_driver);
+}
+
+static void ds3234_unregister_driver(void)
+{
+ spi_unregister_driver(&ds3234_driver);
+}
+
+#else
+
+static int ds3234_register_driver(void)
+{
+ return 0;
+}
+
+static void ds3234_unregister_driver(void)
+{
+}
+
+#endif
+
+static int __init ds323x_init(void)
+{
+ int ret;
+
+ ret = ds3232_register_driver();
+ if (ret) {
+ pr_err("Failed to register ds3232 driver: %d\n", ret);
+ return ret;
+ }
+
+ ret = ds3234_register_driver();
+ if (ret) {
+ pr_err("Failed to register ds3234 driver: %d\n", ret);
+ ds3232_unregister_driver();
+ }
+
+ return ret;
+}
+module_init(ds323x_init)
+
+static void __exit ds323x_exit(void)
+{
+ ds3234_unregister_driver();
+ ds3232_unregister_driver();
+}
+module_exit(ds323x_exit)
MODULE_AUTHOR("Srikanth Srinivasan <srikanth.srinivasan@freescale.com>");
-MODULE_DESCRIPTION("Maxim/Dallas DS3232 RTC Driver");
+MODULE_AUTHOR("Dennis Aberilla <denzzzhome@yahoo.com>");
+MODULE_DESCRIPTION("Maxim/Dallas DS3232/DS3234 RTC Driver");
MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:ds3234");